To segregate the chromosomes faithfully during cell division, cells assemble a spindle that captures the kinetochores and pulls them towards opposite poles. Proper spindle function requires correct interplay between microtubule motors and non-motor proteins. Defects in spindle assembly or changes in spindle dynamics are associated with diseases, such as cancer or developmental disorders. Here, we compared mitotic and meiotic spindles in fission yeast. We show that, even though mitotic and meiotic spindles underwent the typical three phases of spindle elongation, they have distinct features. We found that the relative concentration of the kinesin-14 family protein Pkl1 is decreased in meiosis I compared to mitosis, while the concentration of the kinesin-5 family protein Cut7 remains constant. We identified the second kinesin-14 family protein Klp2 and microtubule dynamics as factors necessary for proper meiotic spindle assembly. This work defines the differences between mitotic and meiotic spindles in fission yeast Schizosaccharomyces pombe, and provides prospect for future comparative studies.

This article has an associated First Person interview with the first author of the paper.

为了在细胞分裂过程中忠实地分离染色体，细胞组装一个纺锤体，捕捉动粒并将它们拉向相反的两极。正确的纺锤体功能需要微管马达和非运动蛋白之间的正确相互作用。纺锤体装配缺陷或纺锤体动力学变化与癌症或发育障碍等疾病有关。在这里，我们比较了裂变酵母中的有丝分裂和减数分裂纺锤体。我们表明，尽管有丝分裂和减数分裂纺锤体经历了纺锤体伸长的典型三个阶段，但它们具有明显的特征。我们发现，与有丝分裂相比，减数分裂 I 中 kinesin-14 家族蛋白 Pkl1 的相对浓度降低，而 kinesin-5 家族蛋白 Cut7 的浓度保持不变。我们确定了第二个 kinesin-14 家族蛋白 Klp2 和微管动力学作为适当减数分裂纺锤体组装所必需的因素。这项工作定义了裂变酵母中有丝分裂和减数分裂纺锤体之间的差异Schizosaccharomyces pombe，并为今后的比较研究提供了前景。

本文与论文的第一作者进行了相关的第一人称采访。